Rials 4 AHOY gem: SQLite3::SQLException: object name reserved for internal use error

I have been trying to set up Ahoy in my Rails 4 application. The set up was for SQLite. In development it seems to work fine. But When I run my specs I get this error......

    ActiveRecord::StatementInvalid: SQLite3::SQLException: object name reserved for internal use: sqlite_autoindex_ahoy_events_1: CREATE UNIQUE INDEX "sqlite_autoindex_ahoy_events_1" ON "ahoy_events" ("id")

And I can't seem to run it in production on Heroku (which uses PostgreSQL).

So 2 questions:

1. How do I fix this error above and run my tests.

2. How do you go about using this gem in production if it requires a different database set up for PostgreSQL

I am fairly new to this so I apologise if this is simple

This appears to be related but I can't see what the solution is exactly from this...http://ift.tt/1U6jKLF